Quantum Lattice Contraction Induced by Transient Raman Process

TL;DR

This paper explains lattice contraction observed in experiments as a result of a transient Raman process, linking optical transitions to lattice displacements through quantum calculations.

Contribution

It introduces a quantum calculation framework under finite-time boundary conditions to explain lattice contraction via a transient Raman process, providing a new theoretical perspective.

Findings

Lattice contraction can be explained by a transient Raman process.

Quantum calculations reveal direct connection between optical transitions and lattice displacements.

The model accounts for observed coherent phonon phenomena.

Abstract

The lattice contraction phenomenon found in time resolved X-ray diffraction and electron diffraction experiments is usually considered to be caused by photo-generated carriers. However, the quantum calculation under finite-time boundary conditions leads to a transient Raman process that directly connects optical transitions and lattice displacements. The lattice contraction phenomenon and the coherent phonon phenomenon can be explained well by the process.